EWX2264 - The Great Hall, Portland Castle; tree-ring analysis 2000

The main beam supporting the upper floor of the octagonal hall of the castle was sampled for dating as part of a wider English Heritage study on the site being undertaken during extensive repairs. The samples taken gave a felling date between AD 1503 and 1535. This investigation was somewhat unusual in that the request was to date a single timber. The beam in the Great Hall was thought to date to the original construction of the castle, known to have taken place during the reign of Henry VIII, around AD 1538 - 40. Two cores were taken from the beam. The heartwood-sapwood boundary was evident on both cores, and the most likely felling date range for the timber was found to be AD 1503 - 35. This shows that the beam in the Great Hall is almost certainly original, and that it may possibly have been cut a few years before being used. Analysis of further timbers from this site may allow clarification of this interpretation.